arch-vega: Fix MUBUF out-of-bounds case 1

Ported from https://gem5-review.googlesource.com/c/public/gem5/+/51127:

This patch updates the out-of-bounds check to properly check
against the correct buffer_offset, which is different depending
on if the const_swizzle_enable is true or false.

Change-Id: I9757226e62c587b679cab2a42f3616a5dca97e60
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/55464
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
1 file changed